NG+ is literally a category, with the goal of killing moonlord on a fresh world, it's on the Category Extensions board. As for individual bossfights, probably not going to happen. The records would be 1 tick kills anyway, look at MappyGaming on Youtube.

I personally like this idea, but when you'll get Zenith, run would has a few seconds. Better would be fighting with them on NG+ with the weapons, which you can get at the part of the game eg fighting with Eye of Cthullu with platinum/gold bow with jesters arrows, but I don't think moderators would add this and you can always run it without sumbitting it on speedrun.com and have it personally on your PC 🙂

This is in fact a speedrun leaderboard, not a speedkill leaderboard, we won't be adding speedkill categories as far as I'm concerned.